$.ajax({
    url: "/test/err/getAjaxError",
    type: "POST",
    async: false,
    success: function(data){
        console.log(data);
        if(data.status == 200 && data.msg == "OK"){
            alert("SUCCESS!");
        } else {
            alert("ERROR!");
        }
    },
    error: function(response, ajaxOptions, thrownError){
        alert("AJAX ERROR!");
    }
})